1. Field of the Invention
This invention relates generally to bookbinding and, more particularly, to a device for scoring a flat spine cover, and binding the publication with a saddle stitch.
2. Description of the Related Art
Scoring, collating, binding, and trimming systems are thoroughly conventional in the printing industry. Such systems must be capable of efficiently producing, in high volume and at high speeds, books of various numbers of pages formed of paper stock of different sizes, weights and finishes.
Books are ordinarily composed of "signatures." A signature is simply a folded sheet presenting four pages (two sheets) of the book. In the instance of small books such a magazines, newspaper supplements, entertainment guides, catalogs of limited size and the like, the signatures to comprise the book are fed from supply hoppers and are gathered, one atop another, on a conveyor or gathering chain. The signatures are stored in a supply stack in signature feeders, which are aligned in rows of multi-unit sections, also known in the art as "boxes" or "pockets." Each of these signature feeders extracts a single folded signature from its supply stack, opens the signature and delivers it, with its fold in draped fashion upon a collating gathering chain which travels directly in front of the aligned signature feeders. Such feeders are well known and are disclosed, for example, in U.S. Pat. No. 2,251,943 issued Aug. 12, 1941, to Kleineberg. The conveyor delivers each group of signatures below a cover scoring and folding device, where a scored and folded cover is fed atop each group of signatures constituting an unbound book on the gathering chain. The covered, unbound books are further carried by gathering chain to a binding station, where a stitch is inserted or an adhesive is applied to he gathered signatures to complete a bound book. Once bound, the gathering chain transports he books to a trimming device, which trims excess from the unbound edges of the newly-formed book. The completed books are then stacked.
A large portion of the bookbinding market is for booklets of one-quarter inch thickness or less. In the binding of magazines and books of magazine thickness, two types of bindings are in use. The most common type of binding for such booklets is referred to as conventional "saddle binding," in which all of the signatures and the cover, are folded in the middle to form a V-shaped spine, gathered together, and bound by a saddle stitch; i.e., two staples at the vertex of the V-shaped spine. A known variation of saddle binding enables the use of a flat spine or back which is of squarish cross section. In this variation, the signatures are sewn together at their vertex, and then glued to the spine inside the cover. This variation is quite costly, however, relative to conventional saddle stitching and is more like "perfect binding" explained below.
The second type of binding, referred to in the art as "perfect binding," typically occurs when a series of folded signatures are stacked flatly one on top of another to form a flat spine, with the stacked signatures being subsequently glued together along the bound edge. Perfect binding is more costly than conventional saddle binding, but is the binding of choice when it is necessary to put any printing on the spine so that, for example, a title of a book could be read while the booklet is on a shelf It is also known to secure a perfect binding in a thinner book by stitches or staples which are disposed adjacent to the spine and perpendicular to the plane of the cover. The production of perfect bound copies calls for a different type of binding machine, also quite costly, and similarly requires trimming and stacking as the final production steps.
Saddle binders are intended for high production, on the order of 15,000 books per hour or more, and comprise a number of subassemblies integrated for synchronous operation. Such unitized machines are quite costly and generally include a signature feeder, a cover folder and feeder, a saddle, a caliper, a stitcher, a delivery bed, a trimmer, and a continuous conveyor assembly or gathering chain for servicing delivery to each subassembly.
The most pertinent prior art known to applicants is listed herewith in numerical order with no significance intended to the ordering.
U.S. Pat. No. 1,196,912 to Weck describes a self-contained mechanism capable of scoring a paper along parallel lines spaced apart by any distance. This device, however, does not incorporate or suggest the use of a saddle stitch in order to simplify the binding process.
U.S. Pat. No. 1,525,238 to Hurd describes an apparatus for slotting and scoring box-board materials with a pair of slotting blades spaced apart by a prescribed distance.
U.S. Pat. Nos. 5,045,045 and 5,133,235 to Davenport et al. describe a combination skip-score skip-perforator apparatus through which a web is fed. The scoring/perforating apparatus includes first and second roller attachments, one of which has a scoring or perforating blade, and the other has a resilient abutment portion for engaging the blade.